So I am working on my second solid silver ecig. My first attempt was a huge failure. I made it work, but it is far from perfect and is not soldered. The part i am having trouble with is the tube itself. I can get it formed, and i can get it to the point where it is holding itself pressed end to end, but the solder itself.... Not so lucky. My first one i tried so many things that i destroyed the edges. I tried using hard, medium, and easy solder pastes. I tried using homemade solder, mixed to be 65% silver, 20% copper, 15% zinc. I used boric acid, borax, and regular pipe fluxes. Pipe flux i know now can't take the heat. I thought i had the seam immaculate. But the solder would not go to the seam. It went everywhere else, but where i needed it to go. Out of frustration, i tried using WAY too much solder. Figured I'd just sand it down and that way i knew it would be in the seam. Nope. It stuck fine to each side of the silver, but not the seam. Like i said, i ended up destroying the edges. I had to hammer out a piece of sheet to fill the void, and all i did was shape it and the end caps hold it in place. The tube i am trying to make is approximately 6" long and a little over an inch in diameter. This time i am using 18 or 20 awg sheet silver. Hoping thicker will be easier to solder. I will include a picture of the first one. It is fully functional and it is my main all day device. It is 100% mechanical, there is no electronics to it. I designed and made the button assemblies myself. The white are Styrofoam that i dissolved in acetone and added cornstarch to, to make my own plastic clay. The blue is a polymer i made from scratch based out of polyvinyl acetate. The spring is magnets. One embedded in the plastic behind the contacts, and there are a few more embedded in the plastic that keep the button from flying out as well. The button is a piece of glass tube, and two pieces of silver, on per end. The silver pieces have magnets glued to them. One functions as the spring, and the other holds the ends on the tube. There are smaller magnets attached to them magnets inside the glass tube to balance the magnetic fields perfectly so the button springs and doesn't fly out. I am using LiFePo4 chemistry 26650 stacked batteries in it. These are safe batteries. You find this exact type inside car jump starters. I have had them get shorted out in copper mods i made, and they melted every bit of plastic on the ecig, and were amazingly hot, but never did they fail or blow up. Them batteries still work great too. I have 72 of these batteries. So any help or advise on this solder would be great. I am using a propane torch mostly. I have an oxy-mapp torch, but it is just too hot. And the piece is so big, my butane torches don't cut it. Trying to keep the whole piece hot, propane has felt like the best option, in my opinion.

That's a large piece to solder. You need lots of heat, clean metal and well-practiced torch control. use Easy solder and a good paste flux. I'd recommend binding the seam together with binding wire as well.

Rule 1, solder will not fill an opening. You have got to find a way to get that joint closed or the solder will not fill in. If you have a big overlap, I'm thinking the inner end is not nearly as hot as the outer flap. You need to get everything to reach the solder's melting point at the same time or the solder will only go to where the heat is.Steve

I recommend using a kiln or an oven to heat the whole piece. Use binding wire to hold it together. Don't forget to use a fine file at the ends and then wipe down with alcohol. There is a paste solder the you can use for different metal and does look like silver. Or id it doesn't mess with components you could use copper foil tape on the inside after its cleaned and just heat up sections at a time but not to hot then use a soldering iron and flux that has zinc, copper, silver flux lead free or just copper & silver. If you use an iron you really dont have to heat up the piece but some do. I would also use a barrier liquid to keep it off of what you dont want soldered just for protective measure. Good luck.

Most soldering is done with 2 edges touching. Since this is 2 surfaces it is going to be much different. Try to cut down the overlap as the inner flap will be hard to heat. I would wire up the cylinder sort of life you would a roast with string, except a hell of a lot tighter. Then I would look for easy wire solder and a paste flux. The torch is going to have to be larger because of the size of the piece. Start at one end and work your way to the other. If you haven't worked with wire solder practice before you work on the big piece. This is one big tube you are making. If you use iron binding wire, don't quench after soldering as the iron will coat your piece.Needless to say...good luckSteve

Slabbercabber, I've never seen silver tubing available in such a large size, so I'm skeptical of that idea, but if it exists, please advise where as I'd love to know.

I think at this point that your best bet is to find out if there is a local metalsmithing studio with directed studio time near you. A good studio will have better torch options for you and an instructor who can watch you while you work and figure out where it is going wrong so that you end up with a product you are happy with and know what to do going forward. In my opinion, the thicker silver will make it harder, not easier. I also can't see why you think the other torch is too hot. When I made a hinged very large cuff bracelet with an oxy/acetylene torch and 16-18 gauge Sterling, I found it took an insanely long time, even after setting up kind of a heat box to reflect the heat back, to get the entire thing up to temperature so I could get it to flow and I actually had to solder one part of the clasp again as it was just tacked at one spot. I would think a propane torch would be considerably lower in temp, so would be even more difficult to get it up to temperature across the entire seam at once. As far as binding wire goes, some people seem to be talking about using titanium now because it won't get solder onnit or contaminate. I did use white out so the solder wouldn't flow into areas I wanted to protect, but found cleaning out the stain it makes in corners and along edges was difficult, even with wire wheels.

i agree with illeney, also, could you not set up 3 to 4 torches with bushy flames in line with the seam and heat all at once? or do like in 'forged in fire' and heat your piece in the type of oven/heat box they use? or heat your piece in 3 sections and using extra hard or hard solder then medium then easy solder. or using hard solder on both ends and easy in the middle? might warp the piece but it may work. clean up may be a bich. whatever you try i will be interested in knowing the results. good luck!